Independent developer Timelock Studio and Serious Sam 4 developer Croteam have teamed up to unload standalone expansion Serious Sam: Siberian Mayhem into the ongoing adventures of ‘Serious’ Sam Stone! The cold winds of chaos blow onto Steam later this month when Serious Sam: Siberian Mayhem launches on January 25.

Make your way through the vast Russian landscapes in five massive new missions set along Arctic coastlines, desolate forests, abandoned villages, and a chilling ghost town. A new set of dangerous foes and bosses join the Horde including some of the most advanced and intimidating creatures the hallowed FPS series has ever seen. Lock and load new weapons like the experimental crossbow or jump into vehicles from snowmobiles to towering mechs.

Serious Sam: Siberian Mayhem took an unusual path, starting as an ambitious project from longtime Serious Sam community modding team Timelock Studio, it quickly evolved into a standalone expansion under the guidance of Croteam.

Serious Sam fans can preorder Serious Sam: Siberian Mayhem on Steam today with Serious Sam 4 owners receiving a sizable discount on a preorder or post launch purchase.